Flash Flood Warning 140, NWS Honolulu, HI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 PM HST MON OCT 16 2006

.SYNOPSIS... A COLD FRONT OVER MAUI COUNTY AND REMNANTS OF FORMER
TROPICAL DEPRESSION FOUR-C WILL PRODUCE HEAVY SHOWERS AND
THUNDERSTORMS ACROSS THE BIG ISLAND TONIGHT. THE HEAVY SHOWERS ARE
EXPECTED TO PRODUCE FLOODING ACROSS THE BIG ISLAND AND SEVERE
THUNDERSTORMS ARE POSSIBLE AS WELL. A SECOND COLD FRONT WILL REACH
KAUAI TONIGHT AND MOVE TO NEAR OAHU ON TUESDAY. WINDS ARE EXPECTED
TO REMAIN RATHER LIGHT FOR THE LATTER HALF OF THE WEEK AS A WEAK
SURFACE TROUGH REMAINS NEAR THE ISLANDS.

&&

.DISCUSSION...A RATHER BUSY EVENING ALREADY WEATHER WISE ACROSS THE
BIG ISLAND AS A COLD FRONT AND REMNANTS OF FORMER TROPICAL
DEPRESSION FOUR-C ARE PRODUCING HEAVY SHOWERS AND THUNDERSTORMS OVER
THE ORCHID ISLE. EARLIER THIS EVENING...THERE WERE SEVERE
THUNDERSTORM SIGNATURES ON SATELLITE AND RADAR IMAGERY WHICH
PROMPTED TWO SEVERE THUNDERSTORM WARNINGS...A RARITY ANYWHERE IN
THE STATE. WEATHER OBSERVERS AND SURFACE OBSERVATIONS ALSO REPORTED
PERIODS OF CONTINUOUS THUNDERSTORMS AND LIGHTNING.

THE COLD FRONT IS ORIENTED SOUTHWEST TO NORTHEAST AND ALTHOUGH IT
IS CURRENTLY OVER THE BIG ISLAND...THE HEAVIEST SHOWERS ARE OVER
THE BIG ISLAND IN ASSOCIATION WITH THE CONVERGENT SOUTHWEST FLOW.
MOISTURE ASSOCIATED WITH THE REMNANTS OF FORMER TROPICAL DEPRESSION
FOUR-C IS PROVIDING THE FUEL FOR THE HEAVY SHOWERS AND
THUNDERSTORMS...WHICH ARE BEING SUPPORTED BY A WELL DEFINED AND
VIGOROUS TROUGH ALOFT. THE THREAT OF HEAVY SHOWERS AND THUNDERSTORMS
WILL CONTINUE FOR THE BIG ISLAND TONIGHT AND TUESDAY.

WE ARE ALSO WATCHING A SECOND THOUGH WEAKER FRONT NORTHWEST OF
KAUAI. LIGHTNING SENSORS INDICATE A FAIRLY ACTIVE FIELD OF
THUNDERSTORMS BEHIND THE FRONT. THIS FRONT HAS SLOWED ITS PROGRESS
TOWARD KAUAI...IN RESPONSE THE SLOWING OF THE MAIN FRONT OVER THE
BIG ISLAND. NONETHELESS...THUNDERSTORMS ARE A DEFINITE POSSIBILITY
FOR KAUAI TONIGHT AND OAHU TOMORROW.

MODELS INDICATE A SURFACE LOW FORMING ALONG THE FRONT NORTHEAST OF
THE BIG ISLAND TOMORROW AND MOVING NORTHWARD THEREAFTER.
UNFORTUNATELY...THIS MEANS THE FRONT WILL STALL NEAR THE BIG ISLAND
FOR POSSIBLY ANOTHER 12 TO 18 HOURS...MAINTAINING THE THREAT OF
HEAVY SHOWERS AND THUNDERSTORMS THROUGH MOST OF TUESDAY.

UNSTABLE CONDITIONS WILL PERSIST ACROSS THE STATE FOR THE NEXT FEW
DAYS AS A LOW/TROUGH ALOFT PARKS ITSELF NEAR THE ISLANDS. AS THE
SURFACE FRONTS DISSIPATE AND TROUGHS LINGER...WINDS WILL REMAIN
LIGHT AND THERE WILL LIKELY BE A TRANSITION TOWARD INTERIOR
CONVECTION OVER THE ISLANDS EACH AFTERNOON. HOWEVER...LETS TAKE
CARE OF THE WEATHER AT HAND FIRST. BIG ISLAND RESIDENTS ARE URGED
TO STAY TUNED TO MEDIA OUTLET AND NOAA WEATHER RADIO FOR THE LATEST
INFORMATION REGARDING WATCHES WARNINGS AND ADVISORIES.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SEVERE THUNDERSTORM WATCH THROUGH 1 AM TUESDAY FOR THE BIG ISLAND
AND SURROUNDING COASTAL WATERS.
FLASH FLOOD WATCH THROUGH TUESDAY AFTERNOON FOR MOLOKAI-LANAI-
KAHOOLAWE-MAUI-BIG ISLAND.
GALE WARNING TODAY FOR THE OFFSHORE WATERS NORTHEAST OF THE
BIG ISLAND.

&&

TANABE